Combination screw and centrifugal submergible pump



Nov. 16, 1965 F. H. sPRlNGl-:R

COMBINATION SCREW AND CENTRIFUGAL SUBMERGIBLE PUMP 7 Sheets-Sheet lFiled Aug. s, 1963 INVENTOR.

MMF'

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Nov. 16, 1965 F. H. SPRINGER COMBINATION SCREW AND CENTRIFUGALSUBMERGIBLE PUMP 7 Sheets-Sheet 2 Filed Aug. 8, 1963 H MR w WO E onT EPm A JW J H1 M w on F. 0 M W F Y B r l f Pi ^\\JN`N` L w Nov. 16, 1965F. H. SPRINGER COMBINATION SCREW AND CENTRIFUGAL SUBMERGIBLE PUMP 7Sheets-Sheet 3 Filed Aug. 8: 1963 Nov. 16, 1965 F. H. SPRINGERCOMBINATION SCREW AND CENTRIFUGAL SUBMERGIBLE PUMP 7 Sheets-Sheet 4Filed Aug. 8, 1953 m505/MX H, SPR/W55? INVENTOR.

MAM /V 7 Nov. 16, 1965 F. H. sPRlNGl-:R 3,217,554

COMBINATION SCREW AND CENTRIFUGAL SUBMERGIBLE PUMP Filed Aug. 8, 1963 '7Sheets-Sheet 5 Femm/[k H, JMP/N55? INVENTOR, l I8 Nov. 16, 1965 F. H.SPRINGER COMBINATION SCREW AND CENTRIFUGAL SUBMERGIBLE PUMP Filed Aug.8, 1963 7 Sheets-Sheet 6 l i I ...lill

INVENTOR.

/f/J A65/V7' Nov. 16, 1965 F. H. SPRINGER 3,217,654

COMBINATION SCREW AND CENTRIFUGAL SUBMERGIBLE PUMP Fled Aug. 8, 1965 7Sheets-Sheet '7 United States Patent O "ice 3,217 654 COMBINATION SCREWAND CENTRIFUGAL SUBMERGIBLE PUMP Frederick Howard Springer, Rte. 1, HaleCenter, Tex. Filed Aug. 8, 1963, Ser. No. 300,796 8 Claims. (Cl. 10S-88)This invention relates to improvements in pumps and more particularly toa portable, centrifugal pump which is ycapable of being moved over theterrain by mobile power, and which may be submerged in a body of waterto enable the water to be lifted to a higher elevation, without loss ofpower while lifting the water by suction to the pump before the water isdischarged into a conduit. The present pump is particularly adapted toirrigation purposes and to other uses which require lifting a largevolume of water.

An object of this invention is to provide a pump in which substantiallyall the power is utilized to perform the lifting action.

Another object of the invention is to provide a centrifugal pump whichutilizes a suction conduit to raise water from a point below the pump tothe pump, or the pump suction conduit and the pump may be submerged inthe water that is to be pumped.

A further object of the invention is to provide a pump which combinesthe characteristics of a centrifugal pump and a screw pump, so as toeliminate a low pressure area at the inlet end of the impeller blades bythe utilization of a spiral screw impeller element which will maintain acharge of liquid in this area which is equal to or in excess of thecapacity of the pump.

Still another object of the invention is to provide a pump, the housingof which does not require packing glands or a bearing support for ashaft transversely through the housing.

Yet another object of the invention is to provide, in a pump, a statorelement to introduce liquid into the pump in a swirling motion so as tolessen the amount of impact on the impeller blade, which will give apump of greater capacity than a conventional pump of the same size.

A still further object of the invention is to provide, :in a pump, astator vane which is so arranged as to present a cutting edge which isin shearing relation with the vanes of the screw element, so foreignmatter, such as weeds, stalks, animal matter, and the like, which aredrawn into the pump will be chopped into bits, thereby preventingc-logging of the pump.

With these objects in mind, and others which will become manifest as thedescription proceeds, reference is to be had to the accompanyingdrawings in which like reference characte-rs designate like parts in theseveral views thereof, in which:

FIG. l is a sectional view of a body of water, showing a mobile pump,which has a power unit attached thereto, positioned in the water so asto withdraw water from the body of water and direct it upward andoutward through a conduit, with portions being shown in dashed outlineto show the position of the discharge conduit;

FIG. 1A is an enlarged top plan view of a fragmentary portion of atrailer frame and tubular element, showing a drive shaft and universaljoints therein;

FIG. 2 is a side elevational view of the pump and power unit adjusted inposition for movement over the terrain, and showing the unit attached toa trailer connection for such movement;

FIG. 3 is a sectional view taken on the line 3-3 of FIG. 2, looking inthe direction indicated by the arrows, to show the manner of mountingthe pump on a trailer to transport the pump and conduit, and to enablethe 3,217,654 Patented Nov.. 16, 1965 pump to be raised and lowered withrespect to the terrain;

FIG. 4 is an enlarged, transverse sectional view taken on the line dt ofFIG. 1A, looking in the direction indicated by the arrows, a portion ofwhich is taken through the hinge joint which hinges the trailed portionof the pump to the power unit, the other portion of the view being takenthrough the lock bolt, which lock bolt maintains the trailed portion ofthe pump in locked position with respect to the power unit, either whilebeing pulled over the terrain or while the pump is in position to pumpwater from a body of water;

FIG. 5 is an end elevational view of the centrifugal pump apart from thetrailer and the drive portion of the pump;

FIG. 6 is a sectional view taken on a plane passing longitudinallythrough the axis of the pump housing;

FIG. 7 is a sectional view taken on the line 7-7 of FIG. 8, looking inthe direction indicated by the arrows;

FIG. 8 is a sectional view taken on the line 8 8 of FIG. 5, looking inthe direction indicated by the arrows, with portions being broken awayand portions being shown in full outline to more clearly bring out thedetails of construction;

FIG. 9 is a perspective View of the impeller removed from the housing ofthe centrifugal pump and showing the inlet side of the impeller;

FIG. l0 is a front elevational view, with parts broken away and withparts shown in section, of the inlet end of the impeller;

FIG. 1l is a fragmentary view of a portion of the impeller taken fromthe side opposite that shown in FIG. l0, with part of the plate beingbroken away to show the interior details of construction of the rearside of the impeller;

FIG. 12 is a sectional view taken on the line 12--12 of FIG. 10, lookingin the direction indicated by the arrows, to show the details ofconstruction of the spiral blades, both of the screw portion and of theimpeller portion of the pump, and showing the transition from the screwtype spiral blades to the centrifugal blades, and showing an alternatearrangement of the backing plate to obtain an increase in volume of thepump without changing the diameter of the housing, with the full outlineshowing the front portion of the impeller as machined to give a pump ofsmaller capacity, and with the dashed outline showing the front portionof the impeller as machined to give greater liquid handling capacity tothe pump;

FIG. 13 is a sectional view taken on the line 13-13 of FIG. 10, lookingin the direction indicated by the arrows, to show the details of theimpeller blades at this point;

FIG. 14 is a sectional view taken on the line 14-14 of FIG. 12, lookingin the direction indicated by the arrows;

FIG. 15 is a perspective View of a stationary vane or turbilizerpositioned in the inlet of the pump to direct water therento with aswirling motion so as to shear any portions of animal and/or vegetablematter into short lengths to prevent clogging the pump;

FIG. 16 is a side elevational view of a modified form of pump, showingthe housing with a shaft extending therefrom, with parts being brokenaway and parts being shown in section to bring out the details ofconstruction;

FIG. 17 is an elevational view of the inlet end of the impeller as shownin FIG. 16, but removed from the Pump;

FIG. 18 is a sectional view taken on the line 18-18 of FIG. 17, lookingin the direction indicated by the arrows;

FIG. 19 is a sectional view taken on the line 19-19 of FIG. 18, lookingin the direction indicated by the arrows, and showing the impellerblades only;

FIG. 20 is a front elevational view of a combination cutting element andscrew impeller which may either be made integral with or secured to thecentrifugal pump impeller so as to enable the cutting action andcharging action of the screw impeller of the centrifugal pump; and

FIG. 21 is a side elevational view of the combination screw typecharging impeller and cutter element as used in the form of the pumpshown in FIGS. 16 to 19, and showing how the screw type impeller may bemade separately from the centrifugal impeller portion and t thereintoand be secured therein as by welding, casting or pressing, or by othersuitable means.

With more detailed reference to the drawing, the numeral 1 designatesgenerally a power unit which, in the present instance, is an internalcombustion engine mounted on a trailer unit 2, which trailer unit may beattached to a trailer hitch 4 on a traction element, such as a truck,tractor or the like.

The power unit 1 has a shaft 6 extending rearward therefrom, which shaft6 has universal joints 8 therein so that the shaft 6 will connect withshaft 10, which shaft 10 extends rearward from the universal joints 8into tubular members 12, which tubular members 12 have bearings 14therein to maintain the shaft 10 in axially aligned relation withrespect to tubular members 12. It is preferable to have the tubularmembers 12 made up in uniform modular lengths and connected together asby bolt flanges 16, which bolt ilanges 16 are faced and piloted toenable the separation thereof to give access to a shaft coupling joint18 which secures lengths of shaft 10 together, thereby enabling a lengthof shaft 10 and the modular lengths of tubular members 12 to be thesame, so when the lengths of shaft 10 are recoupled by shaft couplingjoints 18, the flanges 16 on each end of each modular length of tubularmembers 12 will t together to give a housing for shafts 10 of anydesired length.

A hinge joint is provided intermediate the power unit 1 and the adjacentend of one of the tubular members 12, as will best be seen in FIGS. l,1A, 2 and 4. The power unit 1 has a pair of frame members 23 whichextend rearwardly therefrom. Each of the frame members 23 has a holetherein to receive a pivot pin 22. An arcuate slot 26 is formed in eachframe member 23 to receive bolt 24 therein. The tubular member 12 has aforwardly extending, apertured channel member 25 secured thereto on eachside thereof, which channel members 25 are in overlapping side-by-siderelation, with the respective frame members 23. A pivot pin 22 passesthrough the hole in each of the frame members 23 and through an aperturein each channel member 25 to form a hinge joint.

The bolt 24 passes through the respective apertures in channel members25 and through the respective arcuate slots 26 in frame members 23 toenable the channel members 25 to be secured to the frame members 23, aswill best be seen in FIGS. l, lA, 2 and 4.

Each frame member 23 has an out-turned lug 21 thereon to abut with therespective upper flanges of the channel members 25, when the channelmembers 25 are in aligned relation with the respective frame members 23,so as to hold the channel members 25 in supported relation with respectto frame members 23, for movement of the power unit 1 over the terrain,as shown in FIGs. 2 and 4. The `bolts 24 may be loosened to enable thepump 56 to be backed into a body of water, as indicated at 62, in FIG.l, whereupon, the bolts 24 may be tightened to hold the power unit 1 infixed relation with respect to the channel members 25 and tubular member12.

A support member 28 is connected to the distal end of the outermosttubular member 12 by means of a saddle clamp 30, which saddle clamp 30pivotally mounts a U-shaped member 32, which U-shaped member 32 connectsto the axles 34 of the support member 28. An invertd U-shaped member 36is rigidly connected to the axles 34, so, upon back and forth movementof the U- shaped member 32, which is also connected to the axles 34, theaxles 34 and wheels 38 will be moved back and forth, and `bymanipulation of a winch 40, mounted on a flange 16 on one of the tubularmembers 12, the pump 56 may be raised and lowered with respect to theterrain on which the wheels 38 are located. In order to tighten orloosen the winch line 42, which passes around pulley 44, which pulley 44is xedly secured to the tubular member 12 and thence anchored toinverted U-shaped member 36, as will best be seen in FIGS. 1, 2, and 3,the winch 40 is utilized to wind the winch line 42 thereonto or tounwind the winch line 42 therefrom. This will cause a radius rod 46,which extends forward from axles 34 to move a yoke member 48 alongtubular member 12, and at the extreme forward point of movement, bolts50 in the outermost portion of the flanges 16 pass through apertures 52in the yoke 48, and a nut 54 is secured to each ybolt 5t) to hold theradius rod 46 in rigid relation with respect to the bolts 50.

A centrifugal pump, designated generally at 56, is secured to the distalend of the outermost tubular member 12 with the shaft 74 thereof coupledin axial alignment with shaft 10 which is mounted within tubular member12. The pump 56 has an inlet pipe 58 and an outlet pipe 60 connectedthereto, as will be more fully brought out hereinafter.

With the present arrangement, the device may be moved over the terrain,when arranged in the position as shown in FIG. 2, and when desired, itcan be backed into a body of Iwater indicated at 62 until the pump 56 iswholly or partially submerged, thereby power loss due to suction ofwater from a lower level is eliminated. The inlet pipe 58 has a flange64 thereon, to which flange 64 a conduit or hose may be connected, if itis desired to use the pump 56 above the water level. The outlet pipe 60has a flange 66 thereon for connection of a discharge pipe 68 thereto,which discharge pipe 68 may lead to a higher elevation for discharge, aswill best be seen in FIG. l.

With more specific reference to the pump used in connection with thepresent driving arrangement, the pump 56 is of a character which can becompletely submerged within a body of water, so that the inlet pipe 58,as well as the entire pump 56, will be `below the surface of the water,thereby lessening the power required to lift the water of other liquidbeing pumped.

The present pump 56, as will best be seen in FIG. 8, supports theimpeller, designated generally `by the numeral 70, on a shaft 74 withinpump housing 72. The shaft 74 is journaled in bearings 76 and 78 withina bearing support member 80, which will best be seen in FIG. l5. Thebearing support member has a diffuser vane 82 on each side thereof,which diffuser vanes 82 are secured to a central tubular member 84,which central tubular member 84 is secured to or is made integral with ailange 86 that is bolted to an end 88 of inlet housing 90 by bolts 92.The varied bearing support member 80 has a seal 94 therein whichsurrounds shaft 74 and prevents the passage of water or other liquidthereby. A seal 96 is provided around shaft 74, near the end thereofopposite seal 94, so as to prevent entrance of water or other liquidinto the bearing chamber in which bearings 76 and 78 are mounted. Acoupling 98 is secured to the outer end of shaft 74 and is complementarylto a coupling portion on shaft 10. This will enable shaft 74 to beconnected to shaft 10 and to shaft 6 on the power unit 1 to connect theshaft 74 in driving relation with the power unit.

It is to .be pointed out that the shaft 74 is journaled wholly withininlet housing and merely extends into pump housing 72 and is notjournaled therein, as is the custom with most centrifugal pumps,therefore, a seal and bearing within the pump housing 72 is dispensedwith.

The pump impeller 70 is centrally apertured and keywayed to receiveshaft 74 therethrough, with a key 100 securing pump impeller 70 in fixedrelation with respect to shaft 74. The pump housing 72 has a ring 102surrounding the inlet opening thereof, which ring 102 is secured withinthe inlet opening in close fitting relation, as by a press fit or ashrink lit. The ring 102 has a groove 104 therein to receive a sealingelement 106, such as an Oring 106, therein. The sealing element orO-ring 106 is in contact sealing relation with a ring S which surroundsthe inlet end 110 of pump impeller 70. The ring 108 is secured aroundthe inlet end 110 of the pump irnpeller 70 in close fitting relation asby a press or a shrink t. This arrangement enables the rings 102 and 108to be readily removed and replaced when these become worn, withouthaving to replace an entire housing or an entire impeller because of adefective or Worn seal.

When the pump is operating in a submerged position, the sealing elementor O-ring 106 divides the low pressure area and the high pressure areaof the pump, however, when the pump is used at Ia higher elevation thanthe water level from which it is pumping, the sealing element or O-ring106 prevents the passage of air therethrough which would lessen thesuction of the pump 56.

The diffuser vanes 82 are positioned diametrically opposite each otheron central tubular member 84, with the diffuser vanes lying in a planewhich passes transversely through the axis of the inlet opening of inletpipe 58 and through the axis of shaft 74.

Water drawn into the pump will be divided equally in such manner thateach portion thereof, as it flows past the diffuser vanes into inletpipe 58 of the pump, will be directed into the impeller 70 with acircular motion, due to the curved lips 83 on the terminal ends of therespece tive diffuser vanes 82, which will direct Water into the openingin the inlet end 110 of the pump impeller 70 in such manner as to chargethe pump impeller 70 to capacity into the inlet end of spiral screwvanes 112 of the pump impeller 70, as will best be seen in FIGS. 9, 12,13, and 14. The spiral screw vanes 112 are of the character of a screwpump and will eliminate the low pressure area, which is normal incentrifugal pumps in general. Therefore, with the inlet of the pump,which is usually submerged, being thoroughly charged by swirling waterinto the screw portion of the pump impeller 70, the water is directed bythe screw vanes 1'12 into and through transition spiral vanes 115 to theinterior of the centrifugal portion of the pump into spirally arrangedcentrifugal impeller blades 114. The impeller blades 114 are enclosedbetween a face plate 116 and a removable back plate 118 of the pumpimpeller 70 in such manner as to give denite passages, so the water willbe directed therefrom upon rotation of the pump impeller '70 to directthe water outward into pump housing 72, which pump housing 72 'has apartition 120 therein spirally therearound, for approximately 1S()degrees, to enable water discharged into one segment of the housing 72to take the outermost water course 122, and -the water discharged intothe other segrnent of the pump housing 72 will take the water course'124 so that the water from both the Water courses 122 and 124 willdischarge into the outlet pipe 60 and then into discharge pipe 68 whichleads to the point of use.

Each of the diffuser vanes 82 has a cutting edge 3S thereon which iscomplementary to a cutting edge 113 of spiral screw vanes 112, so whenthe pump impeller 70 is rotated in the direction indicated by the arrow,FIG. 10, twelve cutting actions between the cutting edges 85 on thediffuser vanes 82 and the cutting edges 113 on spiral screw vanes 112will be accorded during each revolution of the pump impeller 70. If thepump impeller 70 is a six blade impeller, it will means that if the pumpimpeller 70 is turning at 2000 r.p.m., there will be 24,000 cuttingactions taking place each minute, therefore, in event vegetation oranimal matter is sucked into the inlet side of the pump 56, it will bechopped into very fine pieces and will thus -be prevented from cloggingthe pump 56 or the conduits which lead therefrom. The above figure isgiven merely for the purpose of illustration, as the pump impeller maybe driven at any desired speed consistent with the size of the impellerand the horse power used to drive the impeller.

As will be best seen in FIG. 12, the back plate 118 of pump impeller 70is screw threaded and is attachably secured to a screw threaded boss 126which enables the pump impeller 70 to be cut away to any thickness, asindicated in FIG. 12, to vary the capacity of the pump 56, and with thescrew threaded boss 126 engaging the screw threads of back plate 113,the back plate 118 may be screwed into place and the back plate tackwelded or otherwise secured to an impeller blade 114 to prevent relativerotation between the pump impeller 70 and the back plate 118. By havingthe patterns constructed in this manner, an impeller rmay be cast forpumps of a variety of capacities, thereby achieving Ia great Vsaving inthe cost of patterns.

FIGS. l0, 11, 12, 13, and 14 disclose minutely the transition of thespiral screw vanes 112 into spiral upright centrifugal impeller blades114. A portion of each of FIGS. 10 and 1l is broken away to show thefront and back respectively of the pump impeller 70 to show thetransition of the spiral screw vanes 112 to the centrifugal impellerblades 114 on the combination dual impeller. It is believed that thisfeature, coupled with the diffuser vanes S2, makes possible the changingof the centrifugal pump to the upmost capacity thereof to give themaximum efficiency of a pump of this character.

It is to be pointed out that the particular relation of the diffuservanes 82 to the screw pump impeller is such that the water is directedin a swirling motion into the screw pump impeller, which is rotating inthe direction indicated by the arrows, FIGS. 9, 10, and 14, so theforward or cutting edge 113 of the respective blades of the screw typeimpeller will rotate to come into shearing relation with the cuttingedges 85 of the ditfuser vanes 82. Each diffuser Vane 02 is curvedadjacent the screw pump impeller vanes 112, as indicated at 83, so thatthe liquid, which is discharged from the inlet pipe 58 into the diffuservanes 82, will be given a swirling motion so it will enter the spiralscrew vanes 112 so as to completely fill the voids between the vaneswith water. With the pump impeller 70 rotating in the directionindicated by the arrows in FIGS. 9, l0, and 14, water will be giveninitial pumping action into the interior of the pump impeller 70 andinto the voids formed between spirally arranged centrifugal impellerblades 114 of the pump impeller 70, which, in turn, will move the wateror other liquid outward by centrifugal force within the spirallyarranged passages into the pump housing 72, with a portion of the wateror other liquid passing into the outer periphery and to the exterior ofpartition 120, with the water in the outer periphery passing into Watercourse 122 between the periphery and the outer wall thereof until thewater is discharged into outlet pipe 60. The water which is dischargedon another segment of the pump for approximately 180 degrees isdischarged inward against partition and follows the water course 124into outlet pipe 60, thereby lessening the turbulence by unloading thepump impeller 70 in different segments of the volute pump housing 72.

Modied form of invention The modified form of the invention, as shown inFiGS. 16 through 19, comprises a volute pump housing '72, FIG. 16, whichis of substantially the same character as the pump housing 72 shown inFIGS.. 1, 2, 5, 6, and 8, and has an outwardly extending inlet housing90, into a side of which an inlet pipe 58 enters. The pump housing 72has an outlet pipe 60 extending outward from the periphery thereof forconnection with a discharge pipe in the manner set out for theaforementioned form of invention.

The pump housing 72 is closed on one side thereof, as indicated at 73,with the flange 91 thereof being of sufcient diameter to close anopening 75 in the opposite side of the pump housing 72. The flange 91 issecured to the housing 72 by means of bolts 93. The opening 75 is ofsuicient size to admit the pump impeller 70 or 70a thereinto, as thepump impeller, as shown in FIGS. 17 through 19, may be madeinterchangeable with the pump impeller shown in the above described formof the invention. The outwardly extending inlet housing 90 has a flangeor end 88, which end S8 is complementary to flange 16, thereby enablingthe pump 56 to be connected in driving relation with a suitable powerunit, such as shown in FIGS. l and 2. The tubular member 12, on whichange 16 is mounted7 has bearings therein to support shaft 10 in aligneddriving relation with the pump 56. The pump impeller 70a has a backplate 151 made integral therewith and integral with varies 152, whichvanes are spirally arranged about the axis thereof in a conventionalmarmer. An outer cover plate 154 is made integral with vanes 152 so thatthe space between the vanes will form passages for the passage of wateroutward therethrough. An outwardly extending end or collar 156, which issimilar in construction to the inlet end 110 of the aforementioned formof the invention, forms a seal with a sealing element, such as an O-ring106. A screw type, vaned impeller 158 is fitted within the openingformed within the inlet end 156 and is secured therein, as by welding orthe like, or is made integral with the outer cover plate 154. The screwtype, vaned impeller 1.58, as shown in the present form of theinvention, has three blades 160, each with a leading or sharpened edge162, so as to form a complementary cutting edge with the cutting edge 85of diffuser vanes 82, when rotated in the direction indicated by thearrow in FIG. 20.

By having the removable diffuser vane secured in the inlet end 156 ofpump impeller 70a, the screw type, varied impeller 158 may be readilyremoved and replaced when the edges thereof become so worn that theimpeller can no longer perform the desired function.

The screw type, vaned impeller 158 has a pitch of such character as tocharge the pump impeller 70a to normal capacity, thereby enabling agreater amount of fluid to be pumped than if the pump were not chargedby the screw type, varied impeller 158.

It is preferable to submerge this pump in the same manner as shown forthe form of pump as shown in FIGS. 1, 1A, 2, and 3, so as to get thegreatest eiciency from the pump.

Having thus clearly shown and described the invention, what is claimedas new and desired to be secured by Letters Patent is:

1. A centrifugal pump comprising:

(a) a volute housing,

(l) said volute housing having an opening formed in one axial sidethereof only, which opening forms an inlet opening,

(2) said volute housing having an outlet opening formed in the peripherythereof,

(b) a shaft extending into the inlet opening in said housing,

(c) a vaned impeller mounted on said shaft,

(l) said vaned impeller having a cutting edge formed on the vanes withinsaid inlet opening,

(d) a housing surrounding said shaft and extending outward therefrom,

(l) said outwardly extending housing having an inlet opening formed in aside thereof, and being in fluid communication with said inlet openingin said volute housing,

(e) a bearing support, vaned diffuser member mounted in said outwardlyextending housing,

(l) said vaned diffuser member lying in a plane passing axially throughsaid shaft and medially through said opening,

(2) means securing said bearing support, vaned diffuser member in saidoutwardly extending housing,

(3) each vane of said vaned diffuser member having a cutting edge formedon the terminal end thereof, which cutting edges are adjacent and are incomplementary cutting relation with the cutting edges of said vanedimpeller when said vaned impeller is rotated in one direction, and

(f) at least one bearing mounted within said bearing support, vaneddiffuser member to journal said shaft mounting said impeller within saidhousing wholly from one side thereof.

2. A centrifugal pump, as defined in claim 1, wherein (a) the vanes ofsaid vaned impeller terminate on a plane in the inlet end of saidimpeller, with the inwardly extending portion forming a helical screwwith the terminal ends thereof extending into and connecting withspirally curved blades to form vanes of a centrifugal pump,

(l) said cutting edges on said vaned impeller being a helical screw, and

(b) a closed back plate secured to said impeller so said vanes will formclosed spiral passages.

3. A combination screw and centrifugal pump for pumping liquids, whichpump comprises;

(a) a volute housing,

(l) said volute housing having an inlet opening formed axially in a sidethereof,

(2) said volute housing having an outlet opening formed therein which istangential thereto intermediate the minimum dimension of said volutehousing and the maximum dimension thereof,

(b) a shaft extending into said housing through the inlet openingthereof,

(l) a bearing support mounted on said housing on the inlet side thereof,

(2) bearing means journaled on said shaft in said bearing support forrotation of said shaft about a longitudinal axis of said shaft,

(c) a varied impeller mounted on and secured to said shaft,

(1) said impeller having a front plate and a back plate, which arespaced apart to define a pumping chamber,

(2) said front plate of said impeller having an axial inlet openingformed therein,

(i) said front plate having an outwardly extending cylindrical ring onthe end thereof which surrounds said inlet opening,

(ii) a helical screw vaned impeller attachably secured within saidoutwardly extending ring with the outermost portion of the respectivevaries forming cutting edges, said helical screw varies being inregister with "the inlet opening of said volute housing,

(1n) said helical screw impeller having at least two varies thereon,

(d) centrifugal pump vanes having a spiral of at least degrees, mountedbetween said front and said back plates and extending to the peripheryof said front and back plates,

(e) said back plate being closed at the rear side thereof,

(f) centrifugal pump vanes positioned between said front plate and saidback plate and being in abutting relation therewith, and extending in aspiral-like patternto the periphery of said impeller plates, and

(g) said bearing support having a varied member mounted thereon andhaving an end thereof in complementary curved relation to the helicalscrew impeller varies,

(1) the adjacent end of said vaned member having at least one cuttingedge thereon which will be 1n complementary cutting relation with thecutting edge of the end of Said helical screw impeller vanes when saidpump impeller is turned in a direction to pump liquid and foreign mattertherethrough so as to cut said foreign matter into bits upon passinginto the inlet of said pump.

4. A centrifugal pump comprising:

(a) a volute housing,

(1) said volute housing having an outlet formed in the peripherythereof,

(2) said volute housing having an inlet opening formed in a sidethereof,

(b) a shaft extending into one side only of said volute housing,

(c) a vaned impeller mounted on said shaft,

(l) the vanes of said impeller terminating on a plane on the inlet endthereof,

(2) the terminal ends of the vanes of said impeller forming cuttingblades,

(d) a housing surrounding said shaft and extending outward therefrom,

(1) said outwardly extending housing having an inlet opening formed in aside thereof, and being in fluid communication with the inlet opening insaid volute housing,

(2) said outwardly extending housing having a first bearing supporttherein,

(i) a first bearing mounted in said first bearing support in saidoutwardly extending housing, and journaling -said shaft for rotation,

(e) a vaned diffuser member mounted in said outwardly extending housingand forming a second bearing support,

(1) said vaned diffuser member lying in a plane passing axially throughsaid shaft and medially through said inlet opening,

(2) means securing said vaned diffuser member forming said secondbearing support in said outwardly extending housing,

(3) a second bearing mounted in said second bearing support and being inaxial alignment with said first bearing and journaling said shaft forrotation and to support said shaft mounting said impeller within said-housing wholly from one side thereof,

(4) the terminal ends of said vanes of said vaned diffuser memberadjacent said impeller blades 'being curved to form cutting edges whichare complementary to the cutting edges of the irnpeller vanes, and

(i) said terminal ends of said vanes of said vaned diffuser Amemberlying substantially in the same plane as the terminal ends of the vanesof said impeller.

5. A centrifugal pump comprising:

(a) a volute housing,

(1) said volute housing having an outlet formed in the peripherythereof,

(2) said volute housing having an inlet opening formed in a sidethereof,

(b) a shaft extending into one side only of said volute housing,

(c) a vaned impeller mounted on said shaft,

(1) said vaned impeller having a back plate de tachably secured to aside thereof,

(2) means varying the out-put capacity of said impeller by varying thedistance between said back plate and an end of said vaned impeller,

(d) a housing surrounding said shaft and extending outward therefrom,

(l) said outwardly extending housing having an inlet opening formed in aside thereof which is in communication with the inlet opening in saidvolute housing,

(e) a bearing support, vaned diffuser member mounted in said outwardlyextending housing,

(l) said vaned diffuser member lying in a plane passing axially throughsaid shaft and medially through said inlet opening in said diffusermember,

(2) means securing said bearing support, varied diffuser member in saidoutwardly extending housing, and

(f) at least one bearing mounted within said bearing support, vaneddiffuser member to journal said shaft, mounting said impeller, withinsaid housing wholly from one side thereof.

6. A centrifugal pump, as defined in claim 5, wherein (a) said vanedimpeller has an outwardly extending screw threaded boss on the back sidethereof, and (b) said backing plate is screw threaded to complementallyengage said screw threaded boss. 7. A combination screw and centrifugalpump for pumping liquids and solids that may be entrained therein whichpump comprises;

(a) a volute housing,

(l) said volute housing having an inlet opening formed axially in a sidethereof,

(2) said volute housing having an outlet opening formed therein which istangential thereto intermediate the minimum dimension of the volutehousing and the maximum dimension thereof,

(b) a shaft extending into one side only of said volute housing,

(1) a bearing support member mounted on said housing on the inlet sidethereof,

(2) bearing means journaling sai-d shaft for rotation about thelongitudinal axis of said shaft,

(c) a vaned impeller mounted on and being secured to said shaft,

(1) said impeller having a front plate and a back plate, which platesare spaced apart to define a pump chamber,

(2) said front plate of said impeller having an axial inlet openingformed therein,

(i) a ring mounted on said front plate of said impeller, which ringextends outward therefrom and surrounds said inlet opening thereof,

(3) said back plate being closed on the rear side thereof,

(d) helical screw impeller vanes positioned within said inlet opening ofsaid vaned impeller and being in register with the inlet opening of saidhousing,

(1) the outer terminal ends of said helical screw impeller vanes extendso as to be substantially flush with the outer end of said ring, whichterminal ends form cutting edges to perform a cutting action, when saidimpeller vanes are rotated in one direction,

(2) said bearing support having a vaned member mounted thereon, an endof each vane thereof being in complementary curved relation to thehelical screw impeller vanes,

(i) the ends of the vanes of said vaned member adjacent the terminalends of said helical screw impeller vanes each having a cutting edgeformed thereon which will be in complementary cutting relation when saidpump impeller is turned in a direction to pump liquid and foreign mattertherethrough, so as to cut the foreign matter into bits upon passinginto the inlet of said pump:

(e) transition vanes connected to said helical screw impeller vanes andbeing unitary therewith and extending toward the back plate of saidimpeller and toward the periphery of said impeller, and

(f) centrifugal pump vanes positioned between said 1 1 front and saidback plates and being in abutting relation therewith, and beingconnected in unitary relation with said transition vanes and extendinginto a spiral-like pattern to the periphery of said impeller plates.

8. A comination screw and centrifugal pump for pumping liquids andsolids that maybe entrained therein, which pump comprises:

(a) a volute housing,

(l) said volute housing having an inlet opening formed axially in a sidethereof,

(2) said volute housing having an outlet opening formed therein which istangential thereto intermediate the minimum dimension of the volutehousing and the maximum dimension thereof,

(b) a shaft extending into one side only of said volute housing,

(1) a bearing support member mounted on said housing on the inlet sidethereof,

(2) bearing means journaling said shaft for rotation about thelongitudinal axis of said shaft,

(c) a vaned impeller mounted on and being secured to said shaft,

(1) said impeller having a front plate and a back plate, which platesare spaced apart to define a pump chamber,

(2) said front plate of said impeller having an axial inlet openingformed therein,

(3) said back plate being closed on the rear side thereof,

(i) said vaned impeller being of a size to enenable the back sidethereof to be machined away to vary the volume of liquid which theimpeller will handle, when the back plate is secured thereto,

(ii) said back plate being detachably secured to said vaned impeller,

(d) helical screw impeller vanes positioned within said inlet opening ofsaid vaned impeller and being in register with the inlet opening of saidhousing,

(e) transition vanes connected to said helical screw impeller vanes andbeing unitary therewith and extending toward the back plate of saidimpeller and toward the periphery of said impeller, and

(f) centrifugal pump vanes positioned between said front plate and saidback plate and being in abutting relation therewith, and being connectedin unitary relation with said transition vanes and extending in aspiral-like pattern to the periphery of said impeller plates.

References Cited by the Examiner UNITED STATES PATENTS 944,864 12/1909Holzer 103-111 1,094,836 y 4/1914 De Laval 10.3-111 1,308,108 7/1919Peterson 103-111 2,069,640 2/1937 Beardsley 10?*111 2,371,681 3/1945Durdin 103-111.1 2,664,052 12/1953 Schmidt 103k87 2,749,846 6/1956Karrer 103-87 2,766,697 10/1956 Judd 10388 2,984,189 5/1961 Jekat 103-88ROBERT M. WALKER, Primary Examiner.

LAURENCE V. EFNER, Examiner.

1. A CENTRIFUGAL PUMP COMPRISING: (A) A VOLUTE HOUSING, (1) SAID VOLUTE HOUSING HAVING AN OPENING FORMED IN ONE AXIAL SIDE THEREOF ONLY, WHICH OPENING FORMS AN INLET OPENING, (2) SAID VOLUTE HOUSING HAVING AN OUTLET OPENING FORMED IN THE PERIPHERY THEREOF, (B) A SHAFT EXTENDING INTO THE INLET OPENING IN SAID HOUSING, (C) A VANED IMPELLER MOUNTED ON SAID SHAFT, (1) SAID VANED IMPELLER HAVING A CUTTING EDGE FORMED ON THE VANES WITHIN SAID INLET OPENING, (D) A HOUSING SURROUNDING SAID SHAFT AND EXTENDING OUTWARD THEREFROM, (1) SAID OUTWARDLY EXTENDING HOUSING HAVING AN INLET OPENING FORMED IN A SIDE THEREOF, AND BEING IN FLUID COMMUNICATION WITH SAID INLET OPENING IN SAID VOLUTE HOUSING, (E) A BEARING SUPPORT, VANED DIFFUSED MEMBER MOUNTED IN SAID OUTWARDLY EXTENDING HOUSING, (1) SAID VANED DIFFUSER MEMBER LYING IN A PLANE PASSING AXIALLY THROUGH SAID SHAFT AND MEDIALLY THROUGH SAID OPENING, (2) MEANS SECURING SAID BEARING SUPPORT, VANED DIFFUSER MEMBER IN SAID OUTWARDLY EXTENDING HOUSING, (3) EACH VANE OF SAID VANED DIFFUSER MEMBER HAVING A CUTTING EDGE FORMED ON THE TERMINAL END THEREOF, WHICH CUTTING EDGES ARE ADJACENT AND ARE IN COMPLEMENTARY CUTTING RELATION WITH THE CUTTING EDGES OF SAID VANED IMPELLER WHEN SAID VANED IMPELLER IS ROTATED IN ONE DIRECTION, AND (F) AT LEAST ONE BEARING MOUNTED WITHIN SAID BEARING SUPPORT, VANED DIFFUSER MEMBER TO JOURNAL SAID SHAFT MOUNTING SAID IMPELLER WITHIN SAID HOUSING WHOLLY FROM ONE SIDE THEREOF. 